Ventilation systems

ABSTRACT

A ventilating system for a closed area having at least two vent openings therein. A fan is placed within one vent opening and is driven by a reversible electric motor. A wind direction indicating means is mounted outside of the enclosed area and controls a directional switch which in turn controls the direction of rotation of the motor and the fan. The system is so connected that the fan will move air in the direction of air movement caused by the prevailing wind. There may also be incorporated into the system a temperature switch within the enclosed area and a wind velocity switch without the area.

United States Patent [191 Jones VENTILATION SYSTEMS [76] Inventor: Herman W. Jones, Rte. 2, Box 848, Albany, Ky. 42602 22 Filed: Sept. 30, 1974 2] Appl. No.: 510,177

[52] US. Cl. 236/49; 98/33 R [51] Int. Cl. F24F 7/00 [58] Field Of Search 236/49; 73/l88, 189; 98/39, 32, I4, 43, 33 R [56] References Cited UNlTED STATES PATENTS 359,769 3/l887 Bruette 98/32 37l,l80 lO/l887 Dexter 98/32 X 1,606,659 1l/l926 Moore 98/32 2,l63,692 6/1939 Loepsinger 98/32 X 330L008 4/[974 Wenger 236/49 X [Ill 3,927,828

[ 1 Dec. 23, 1975 Primary E.taminerWilliam E. Wayner Assistant Examiner-William E. Tapolcai, Jr. Attorney, Agent, or Firm-John E. Benoit [57] ABSTRACT A ventilating system for a closed area having at least two vent openings therein. A fan is placed within one vent opening and is driven by a reversible electric motor. A wind direction indicating means is mounted outside of the enclosed area and controls a directional switch which in turn controls the direction of rotation of the motor and the fan. The system is so connected that the fan will move air in the direction of air movement caused by the prevailing wind. There may also be incorporated into the system a temperature switch within the enclosed area and a wind velocity switch without the area.

6 Claims, 6 Drawing Figures US. Patent Dec. 23, 1975 Sheet 1 of2 3,927,828

FIG.2

US. Patent Dec.23, 1975 Sheet2of2 3,927,828

VENTILATION SYSTEMS This application relates generally to ventilation systems and more particularly to systems used for ventilating enclosed areas such as attics and the like.

Attic ventilation systems have been used extensively in the past, and still used under good construction practice as well as being a standard building code requirement in some locations. Such fans are desirable even if the home is air conditioned.

Basically, the system employs a fan installed in one of the two vents which are normally provided in the attic of the average house. The fan is used primarily during the day when roof heat energy absorption is the greatest, but will operate any time under the control of a temperature sensor indicating a predetermined temperature has been reached. It is obvious that the use of an electrically driven fan is much more economical than the continued use of air conditioning units. With the advent of sharply increased costs of fuel, both electric and gas, any substitute for modern air conditioning units will result in a substantial saving.

Fans in use today are normally driven by electric motors in one direction only. Although they may be placed to drive the fan within a vent in the direction of the generally prevailing wind, they provide little, if any, air movement when the prevailing wind is in the direction opposed to the movement of air by the fan. This obviously accomplishes little good while still using energy to drive the fan.

Additionally, most fans in use today employ only an on-off switch which may be manually or thermostatically controlled. Accordingly, if sufficient wind velocity should occur in later hours, the fan will continue to operate even though such operation is not required or desirable.

Accordingly, it is an object of this invention to provide a ventilating system which utilizes a reversible fan.

A further object of this invention is to provide a reversible fan whose direction of rotation is controlled in accordance with the direction of the prevailing wind.

Yet, another object of this invention is to provide a ventilating system employing a reversible fan including means for disconnecting the fan when the wind reaches a predetermined velocity.

These and other objects of the invention will be more clearly understood from the following description when taken in conjunction with the drawings wherein:

FIG. 1 is a schematic diagram of the plan view of an attic enclosure showing various prevailing winds;

FIG. 2 is an electrical schematic view representation of a preferred embodiment of a control system for the present invention;

FIG. 3 is a perspective view of a weather vane employing various switches illustrated in FIG. 2;

FIG. 4 is a partial side view illustrating one type of velocity switch which may be used in the present inven tion;

FIG. 5 is an exploded perspective view of a preferred embodiment of the directional switch used in the present invention; and

FIG. 6 is a view of an alternate wind velocity switch which may be used in the present invention.

Broadly speaking, the present invention relates to a ventilating system for a closed area having at least two vent openings therein. A fan is placed within one vent opening and is driven by a reversible electric motor. A

wind direction indicating means is mounted outside of the enclosed area and controls a directional switch which in turn controls the direction of rotation of the motor and the fan. The system is so connected that the fan will move air in the direction of air movement caused by the prevailing wind. There may also be incorporated into the system a temperature switch within the enclosed area and a wind velocity switch without the area.

Turning now to the specific illustration in the drawings, there is shown in FIG. 1 a schematic plan view of an enclosed area 11 such as an attic in a residential dwelling. Two attic vents 13 and I5 are provided at opposite ends of attic 11. A vent fan 17 is placed within the vent 15 in the normal manner. FIG. 1 illustrates the various problems which arise when the prevailing wind shifts directions. If the wind is from the direction shown by arrow W and the fan is moving in the direction towards vent 13 then the wind and the fan are in cooperation for moving air efficiently through attic 11.

However, if the wind shifts and is from the direction away from vent 13, it is evident that the movement of air by the fan and the movement of air by the wind are in opposing direction, and the movement of air through the attic will be greatly diminished, thus reducing the operating efficiency of the system. If the wind should approach the sides of the attic which do not contain air vents such as shown by arrow W then it will not affect the air movement of the fan.

From the illustration of FIG. 1, it will become clear that the use of a reversible fan whose direction is controlled so as to move air in the same direction as the air being moved by the prevailing wind will obviate the problems discussed above and maintain the efficiency of the overall system regardless of wind direction. Also, it will be clear that the particular direction of the rotation of the fan will not be important if the wind is directed primarily at right angles to the plane of the axis of the fan.

FIG. 2 is a schematic illustration of a preferred embodiment of the electrical control system for the motor which drives the fan. A manual switch I9 is connected between a source of household current, such as llS volts, and the reversible electric motor 21. A transformer 33 is connected across the household current supply beyond the manual switch 19. This transformer provides a step-down voltage so as to provide a low voltage, such as 12 volts, to the control devices which will be discussed below.

Three control circuits are shown connected in series so as to incorporate all of the possible elements which may be used in the system. The primary control element is illustrated as the direction switch 23 having dual contact terminals 22 and 24. These terminals lead to solenoids 30 and 32 respectively. which activate their associated switches 29 and 3|. Whichever of the two solenoid switches is activated determines the direction of rotation of reversible motor 21.

Also connected in series with the wind direction switch 23 is a wind velocity switch 25, and a switch 28 which is coupled to and activated by a temperature sensing unit 27 such as a thermostat.

In the electrical control system of FIG. 2, all switches must be closed in order that the motor 21 will operate. Obviously, if only the wind direction switch is desired, the wind velocity switch and/or the temperature switch may be eliminated from the system.

Turning now to FIGS. 3 and 4, there is illustrated therein embodiments of the wind direction and velocity switches which may be used in the present in ention.

A support 37 is mounted on roof 35 by any wellknown means such as screws or nails (not shown). A weather vane 39 is mounted within the support 37 by means of a vertical rod 41 which is rotatable within the base. A horizontal rod 43 is mounted at substantially right angles at the upper end of the vertical rod 41. One end of the horizontal rod 43 terminates in two plates 45 and 47 which are pivotally mounted to the end of the rod at 51 and 53 respectively. Plates 45 and 47 have a geometrical configuration of a trapezoid so as to provide the required aerodynamic function of a weather vane. If desired, an additional vertical tin 46 may be mounted on one or both plates. If plates 45 and 47 are rotated 90 degrees, the additional fin 46 would be a plan view with the removal of fin 46.

The plates are separate by a compression spring 49 which biases the plates in a direction away from each other in accordance with the selected strength of the spring.

A button 55 is mounted on the underside of plate 45 so that compression of the plates in a direction towards each other will open the contacts of the wind velocity switch 25. The leads from the contacts of switch 25 may be carried within horizontal rod 43 and vertical rod 41 for connection in series with the wind direction switch 23.

FIG. illustrates a preferred embodiment of the wind direction switch 23. A cylindrical base 57 is mounted on support member 37 by any well known means. The upper face of base 57 has two sets of semi-circular contacts 59 and 61 embedded within the base. As illustrated, leads 62 are carried within base 57 and connect with contacts 59. Similar leads (not shown) are also provided for the contacts 61.

The two sets of semi-circular contacts 59 and 61 are separated by means of over-center cams 63 and 65. These cams cooperate with the configuration of the upper section 73 of the direction switch.

The upper section 73 is comprised of a cylindrical section having contacts 75 mounted on protruberance 66 extending downwardly from the lower part of cylinder 73. Leads 67 extend upwardly through cylinder 73 and may extend within rod 41 to connect with the velocity switch discussed above. There is also provided a threaded bore hole 69 through the side of cylinder 73. As shown in FIG. 3 both the base 57 and the upper section 73 fit about vertical rod 41. While the base 57 remains stationary with respect to the rotation of rod 41, the insertion of a screw (not shown) in the bore hole 69 locks the upper section to rod 41 and causes rotation of the upper section therewith.

In operation, movement of the weather vane 39, which indicates the direction of the prevailing wind, will determine which of the two sets of semi-circular contacts 59 and 61 are in engagement with contacts 66. As can be seen from the schematic illustration of FIG. 2, this determines the direction of rotation of the reversible motor and thus the direction of the fan. In order to prevent the control illustrated in FIG. 5 from resting in a non-operative position, the over center earns 63 and 65 are provided on the base to cooperate with the protruberance 66. The weather vane is, in effect, free floating so that the switch can operate properly relative to the gravitational effect of the weather vane.

The illustrated velocity switch of FIG. 4 is a nut cracker switch designed so that the wind velocity required to close the vents is determined by the compression value of spring 49. The purpose of using such a wind velocity switch is one of energy conservation since a wind velocity above a certain value, such as 15 mph, should be sufficient to ventilate the attic without the aid of a fan.

FIG. 6 shows an alternate embodiment of a device which could be used to control the wind velocity switch. There is shown therein a standard anemometer 71 cooperating with a switch which is responsive to the speed of rotation of the anemometer in a well known fashion. Using this device would require an additional piece of equipment within the system.

The temperature sensing device is located within the attic itself and may be set so as to activate or deactivate the fan in accordance with a preselected interior temperature.

It will now become obvious that the present invention provides a highly efficient ventilation system for enclosed areas such as attics and the like. Through the use of controls which effect the operation of a fan to always assist the prevailing wind direction, a much greater volume of air can be obtained in a shorter period of time. Thus, not only is the cooling effect more rapid, less energy is also required to obtain the desired results.

It will be obvious to those skilled in the art that the various components within the system may be substituted by equivalent parts without departing from the invention. Accordingly, the above description and drawings are illustrative only and the scope of the invention is to be limited only by the following claims.

What is claimed is:

l. A ventilating system for a closed area having at least two vent openings therein comprising:

a fan within one of said vent openings;

a reversible electric motor coupled to said fan;

means mounted outside of said closed area for determining the direction of the prevailing wind; a directional switch connected to and controlled by said means mounted outside of said closed area;

means coupling said switch to said motor for controlling the direction of the motor drive in accordance with the direction of said prevailing wind;

means for measuring the prevailing wind velocity;

and

switch means coupled to said means for measuring said wind velocity, said switch means being in series with said directional switch and being deactivated at a predetermined wind velocity.

2. The ventilating system of claim I further comprismg means for sensing the temperature within said closed area; and

switch means coupled to said means for sensing the temperature within said area, said switch means being in series with said directional switch and being deactivated below a predetermined temperature within said area.

3. The ventilating system of claim 1 further comprismg;

means for sensing the temperature within said closed area; and

switch means actuated by said temperature sensing means and responsive to a predetermined temperature and connected in series with said directional switch and said switch means coupled to said means for measuring wind velocity. means for measuring the prevailing wind velocity; 4. A ventilating system for an enclosed area having at and least two vent openings i i means connected between said last named means and said motor for deactivating said motor at a predetermined wind velocity. 5. The ventilating system of claim 4 wherein said said fan; means ford termini th fth direction determining means and said velocity detere g e o e Preva' mg mining means are mounted in a weathervane structure.

6. The ventilating system of claim 4 wherein said means connected beiwee saw last named means and means for measuring the prevailing wind direction and said motor for controlling the direction Of rotation aid means for measuring said elocity are incorof said motor in accordance with the direction of ol-med in a weather vane. said prevailing wind;

a fan within one of said vent openings; a reversible electric motor coupled to and driving (all 

1. A ventilating system for a closed area having at least two vent openings therein comprising: a fan within one of said vent openings; a reversible electric motor coupled to said fan; means mounted outside of said closed area for determining the direction of the prevailing wind; a directional switch connected to and controlled by said means mounted outside of said closed area; means coupling said switch to said motor for controlling the direction of the motor drive in accordance with the direction of said prevailing wind; means for measuring the prevailing wind velocity; and switch means coupled to said means for measuring said wind velocity, said switch means being in series with said directional switch and being deactivated at a predetermined wind velocity.
 2. The ventilating system of claim 1 further comprising means for sensing the temperature within said closed area; and switch means coupled to said means for sensing the temperature within said area, said switch means being in series with said directional switch and being deactivated below a predetermined temperature within said area.
 3. The ventilating system of claim 1 further comprising; means for sensing the temperature within said closed area; and switch means actuated by said temperature sensing means and responsive to a predetermined temperature and connected in series with said directional switch and said switch means coupled to said means for measuring wind velocity.
 4. A ventilating system for an enclosed area having at least two vent openings comprising; a fan within one of said vent openings; a reversible electric motor coupled to and driving said fan; means for determining the direction of the prevailing wind outside of said enclosure; means connected between said last named means and said motor for controlling the direction of rotation of said motor in accordance with the direction of said prevailing wind; means for measuring the prevailing wind velocity; and means connected between said last named means and said motor for deactivating said motor at a predetermined wind velocity.
 5. The ventilating system of claim 4 wherein said direction determining means and said velocity determining means are mounted in a weathervane structure.
 6. The ventilating system of claim 4 wherein said means for measuring the prevailing wind direction and said means for measuring said wind velocity are incorporated in a weather vane. 